|Swift and Styles|
The 'I Knew You Were Trouble' singer split from the One Direction star two weeks ago, but had already organised the treat to celebrate his turning 19 next month.
Taylor had spared no expense on the break, booking five nights at the Palazzina Grassi hotel on the Grand Canal and their own personal transport for the duration of their stay in the romantic Italian floating city.
A source told The Sun newspaper: "Taylor organised an all-expenses-paid trip before the split.
"She even arranged a private gondola for them for the entire time they would be there."
Taylor, 23, and Harry broke up after two months together during a New Year holiday in the Caribbean Virgin Islands. Since then the expensive Christmas gifts they bought each have also been neglected.
The source added: "Taylor isn't using the designer bag he bought her any more. She'd also sorted some exclusive birthday presents for him - new threads from [London's] Savile Row and Beatles memorabilia.
"Harry is pretty gutted about the whole thing, even though he's putting on a cool front. He's touched she went to so much trouble to arrange his birthday ahead of time."
Instead of Venice, Harry is now thought to be planning a trip with fellow teen heartthrob Justin Bieber - who has recently split from his girlfriend, Selena Gomez - which will see them jet to either Las Vegas or Mexico for the US Spring Break holidays.